Opportunities and benefits for increasing transmission capacity between the US eastern and western interconnections

The Value of Increased HVDC Capacity Between Eastern and Western U.S. Grids: The Interconnections Seam Study

“…Production costs include, for new and existing resources, fixed and variable operating and maintenance costs, fuel cost and operational reserve cost (regulation up/down and contingency reserve). Constraints imposed include: power balance at each node; "DC" angle constraints across each existing line; upper and lower limits on generation dispatch and line flows; lower limits on available up/down regulation reserves and available contingency reserves; upper limits on up/down regulation (contingency) reserves by the unit's 1-minute (10-minute) ramp rate; capacity in excess of the NERC-recommended 115% of peak [14] (all units contributed to the planning reserve according to each units capacity value which, for wind and solar, varied locationally as described in [15] but were independent of renewable penetration); and the definition of the particular transmission design being studied. Operational reserves were imposed systemwide; a capacity constraint was imposed in each of four regions:…”

“…This report is available at no cost from the National Renewable Energy Laboratory at www.nrel.gov/publications West, Northwest, Midwest, and East. A full description of the model is available at [15].…”

“…The remaining four conditions were "peak net-load blocks" to capture one-hour annual peak conditions in each of four regions. The peak blocks were used to model the capacity constraint; because different regions peak at different times of the year, this enabled analysis of interregional reserve-sharing subject to transmissionrelated deliverability constraints [15].…”

Scenario Selection for Iterative Stochastic Transmission Expansion Planning

“…We used the same dataset for the U.S. Eastern and Western Interconnections as used in [50] with some modifications. The dataset contained 169 buses, 730 transmission lines, 1640 existing generators, and 1568 candidate generators, representing the transmission infrastructures of the North American power grid.…”

Control of multi-terminal VSC-HVDC systems for combined AC/DC systems to improve power system dynamic performance

“…Similar to Section 4.4.2, the outage of Gen102 (450MW) in A1 of the AC-MTDC test system is used as the contingency to compare different frequency control performances with the proposed As briefly introduced in Section 1.1.3.3, in order to reduce the cost of developing and utilizing the renewable energy resources in the US, such as wind in the Midwest and solar in the southwest, the "Interconnection Seam Study" [36,37,102] proposes to interconnect the asynchronous AC systems via a continental HVDC overlay. Figure 6.1 shows the seams between the three asynchronous AC interconnections in the US, namely the Westerin Interconnection (WI), the Eastern Interconnection (EI) and the Electric Reliability Council of Texas (ERCOT); it also shows and the geographic distribution of different types of renewable resources [12] and the major load centers, which can be seen are typically far away from each other.…”